If A Person Can't Help It
If a person can't help it then they can't help it. If you're going to get irritated at them then it's not going to help anyone. If you can't change the person then change yourself.
Take 5 deep breaths. Slowly breathe in to a count of four and breathe out to the count of four. After you have taken these five deep breaths, tell yourself, "I am strong and in control."
Try to keep calm and cary on with what you were doing.
When your problems are too big it's time to talk to your Parent or Teacher, or both: